As discussed in parent application Ser. No. 077,584, now U.S. Pat. No. 4,343,754, various techniques are known for manufacture of closures for bottles and like containers. More recently, the advantages of the use of plastic closures have been recognized, although problems have been encountered in designing and manufacturing a plastic closure having the requisite strength and sealing capabilities. In this regard, parent application Ser. No. 077,584, now U.S. Pat. No. 4,343,754, discloses a process and apparatus for manufacture of plastic closures which have proven quite successful, and portions of that application not inconsistent with the present disclosure are incorporated herein by reference.
In addition to exhibiting the requisite strength and sealing properties, some closures must be formed with a tamper-indicating pilfer band. Most previously known pilfer band arrangements require that the container to which the closure is applied includes a specially shaped surface for coaction with the pilfer band, or require additional manufacturing steps after the closure is applied to a container so that the pilfer band correctly coacts with the container for indicating closure removal. Thus, formation of a plastic closure having a tamper-indicating pilfer band which overcomes drawbacks in pilfer band arrangements heretofore known is desirable.
Accordingly, a closure-making process and apparatus which facilitate manufacture of plastic closures, and permit closure formation with a sealing liner if desired, with or without a pilfer band, represent a significant advance in the art.